The present invention relates to digitally-programmable amplifiers, more specifically it relates to digitally-programmable transconductance amplifiers.
Digitally-programmable amplifiers find widespread use throughout the electronics industry. They are used for controlling signal amplitude in programmable waveform generators. They can also be used to generate some particular waveforms such as staircase, ramp or triangular with controllable amplitude and frequency. If a recycling counter is used to drive the amplifier control input, one can generate a parabola represented by its time parametric equation. This basic parabola may then be used to generate other conic sections for graphic displays. Other applications include digital filter control and parametric switching and optimization.
Conventional design techniques produce amplifiers which employ saturating transistor switches and require precise control of offset voltages. The resulting amplifiers respond slowly to control inputs and are difficult to calibrate.